1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_FLOW_DISSECTOR_H
3 #define _NET_FLOW_DISSECTOR_H
4
5 #include <linux/types.h>
6 #include <linux/in6.h>
7 #include <linux/siphash.h>
8 #include <linux/string.h>
9 #include <uapi/linux/if_ether.h>
10
11 struct bpf_prog;
12 struct net;
13 struct sk_buff;
14
15 /**
16 * struct flow_dissector_key_control:
17 * @thoff: Transport header offset
18 */
19 struct flow_dissector_key_control {
20 u16 thoff;
21 u16 addr_type;
22 u32 flags;
23 };
24
25 #define FLOW_DIS_IS_FRAGMENT BIT(0)
26 #define FLOW_DIS_FIRST_FRAG BIT(1)
27 #define FLOW_DIS_ENCAPSULATION BIT(2)
28
29 enum flow_dissect_ret {
30 FLOW_DISSECT_RET_OUT_GOOD,
31 FLOW_DISSECT_RET_OUT_BAD,
32 FLOW_DISSECT_RET_PROTO_AGAIN,
33 FLOW_DISSECT_RET_IPPROTO_AGAIN,
34 FLOW_DISSECT_RET_CONTINUE,
35 };
36
37 /**
38 * struct flow_dissector_key_basic:
39 * @n_proto: Network header protocol (eg. IPv4/IPv6)
40 * @ip_proto: Transport header protocol (eg. TCP/UDP)
41 */
42 struct flow_dissector_key_basic {
43 __be16 n_proto;
44 u8 ip_proto;
45 u8 padding;
46 };
47
48 struct flow_dissector_key_tags {
49 u32 flow_label;
50 };
51
52 struct flow_dissector_key_vlan {
53 union {
54 struct {
55 u16 vlan_id:12,
56 vlan_dei:1,
57 vlan_priority:3;
58 };
59 __be16 vlan_tci;
60 };
61 __be16 vlan_tpid;
62 };
63
64 struct flow_dissector_mpls_lse {
65 u32 mpls_ttl:8,
66 mpls_bos:1,
67 mpls_tc:3,
68 mpls_label:20;
69 };
70
71 #define FLOW_DIS_MPLS_MAX 7
72 struct flow_dissector_key_mpls {
73 struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */
74 u8 used_lses; /* One bit set for each Label Stack Entry in use */
75 };
76
dissector_set_mpls_lse(struct flow_dissector_key_mpls * mpls,int lse_index)77 static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls,
78 int lse_index)
79 {
80 mpls->used_lses |= 1 << lse_index;
81 }
82
83 #define FLOW_DIS_TUN_OPTS_MAX 255
84 /**
85 * struct flow_dissector_key_enc_opts:
86 * @data: tunnel option data
87 * @len: length of tunnel option data
88 * @dst_opt_type: tunnel option type
89 */
90 struct flow_dissector_key_enc_opts {
91 u8 data[FLOW_DIS_TUN_OPTS_MAX]; /* Using IP_TUNNEL_OPTS_MAX is desired
92 * here but seems difficult to #include
93 */
94 u8 len;
95 __be16 dst_opt_type;
96 };
97
98 struct flow_dissector_key_keyid {
99 __be32 keyid;
100 };
101
102 /**
103 * struct flow_dissector_key_ipv4_addrs:
104 * @src: source ip address
105 * @dst: destination ip address
106 */
107 struct flow_dissector_key_ipv4_addrs {
108 /* (src,dst) must be grouped, in the same way than in IP header */
109 __be32 src;
110 __be32 dst;
111 };
112
113 /**
114 * struct flow_dissector_key_ipv6_addrs:
115 * @src: source ip address
116 * @dst: destination ip address
117 */
118 struct flow_dissector_key_ipv6_addrs {
119 /* (src,dst) must be grouped, in the same way than in IP header */
120 struct in6_addr src;
121 struct in6_addr dst;
122 };
123
124 /**
125 * struct flow_dissector_key_tipc:
126 * @key: source node address combined with selector
127 */
128 struct flow_dissector_key_tipc {
129 __be32 key;
130 };
131
132 /**
133 * struct flow_dissector_key_addrs:
134 * @v4addrs: IPv4 addresses
135 * @v6addrs: IPv6 addresses
136 */
137 struct flow_dissector_key_addrs {
138 union {
139 struct flow_dissector_key_ipv4_addrs v4addrs;
140 struct flow_dissector_key_ipv6_addrs v6addrs;
141 struct flow_dissector_key_tipc tipckey;
142 };
143 };
144
145 /**
146 * flow_dissector_key_arp:
147 * @ports: Operation, source and target addresses for an ARP header
148 * for Ethernet hardware addresses and IPv4 protocol addresses
149 * sip: Sender IP address
150 * tip: Target IP address
151 * op: Operation
152 * sha: Sender hardware address
153 * tpa: Target hardware address
154 */
155 struct flow_dissector_key_arp {
156 __u32 sip;
157 __u32 tip;
158 __u8 op;
159 unsigned char sha[ETH_ALEN];
160 unsigned char tha[ETH_ALEN];
161 };
162
163 /**
164 * flow_dissector_key_tp_ports:
165 * @ports: port numbers of Transport header
166 * src: source port number
167 * dst: destination port number
168 */
169 struct flow_dissector_key_ports {
170 union {
171 __be32 ports;
172 struct {
173 __be16 src;
174 __be16 dst;
175 };
176 };
177 };
178
179 /**
180 * flow_dissector_key_icmp:
181 * type: ICMP type
182 * code: ICMP code
183 * id: session identifier
184 */
185 struct flow_dissector_key_icmp {
186 struct {
187 u8 type;
188 u8 code;
189 };
190 u16 id;
191 };
192
193 /**
194 * struct flow_dissector_key_eth_addrs:
195 * @src: source Ethernet address
196 * @dst: destination Ethernet address
197 */
198 struct flow_dissector_key_eth_addrs {
199 /* (dst,src) must be grouped, in the same way than in ETH header */
200 unsigned char dst[ETH_ALEN];
201 unsigned char src[ETH_ALEN];
202 };
203
204 /**
205 * struct flow_dissector_key_tcp:
206 * @flags: flags
207 */
208 struct flow_dissector_key_tcp {
209 __be16 flags;
210 };
211
212 /**
213 * struct flow_dissector_key_ip:
214 * @tos: tos
215 * @ttl: ttl
216 */
217 struct flow_dissector_key_ip {
218 __u8 tos;
219 __u8 ttl;
220 };
221
222 /**
223 * struct flow_dissector_key_meta:
224 * @ingress_ifindex: ingress ifindex
225 * @ingress_iftype: ingress interface type
226 */
227 struct flow_dissector_key_meta {
228 int ingress_ifindex;
229 u16 ingress_iftype;
230 };
231
232 /**
233 * struct flow_dissector_key_ct:
234 * @ct_state: conntrack state after converting with map
235 * @ct_mark: conttrack mark
236 * @ct_zone: conntrack zone
237 * @ct_labels: conntrack labels
238 */
239 struct flow_dissector_key_ct {
240 u16 ct_state;
241 u16 ct_zone;
242 u32 ct_mark;
243 u32 ct_labels[4];
244 };
245
246 /**
247 * struct flow_dissector_key_hash:
248 * @hash: hash value
249 */
250 struct flow_dissector_key_hash {
251 u32 hash;
252 };
253
254 enum flow_dissector_key_id {
255 FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
256 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
257 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
258 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
259 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
260 FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
261 FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
262 FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
263 FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
264 FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
265 FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
266 FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
267 FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
268 FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
269 FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
270 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
271 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
272 FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
273 FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
274 FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
275 FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
276 FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
277 FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
278 FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
279 FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
280 FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
281 FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
282 FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
283
284 FLOW_DISSECTOR_KEY_MAX,
285 };
286
287 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
288 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(1)
289 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(2)
290
291 struct flow_dissector_key {
292 enum flow_dissector_key_id key_id;
293 size_t offset; /* offset of struct flow_dissector_key_*
294 in target the struct */
295 };
296
297 struct flow_dissector {
298 unsigned int used_keys; /* each bit repesents presence of one key id */
299 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
300 };
301
302 struct flow_keys_basic {
303 struct flow_dissector_key_control control;
304 struct flow_dissector_key_basic basic;
305 };
306
307 struct flow_keys {
308 struct flow_dissector_key_control control;
309 #define FLOW_KEYS_HASH_START_FIELD basic
310 struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
311 struct flow_dissector_key_tags tags;
312 struct flow_dissector_key_vlan vlan;
313 struct flow_dissector_key_vlan cvlan;
314 struct flow_dissector_key_keyid keyid;
315 struct flow_dissector_key_ports ports;
316 struct flow_dissector_key_icmp icmp;
317 /* 'addrs' must be the last member */
318 struct flow_dissector_key_addrs addrs;
319 };
320
321 #define FLOW_KEYS_HASH_OFFSET \
322 offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
323
324 __be32 flow_get_u32_src(const struct flow_keys *flow);
325 __be32 flow_get_u32_dst(const struct flow_keys *flow);
326
327 extern struct flow_dissector flow_keys_dissector;
328 extern struct flow_dissector flow_keys_basic_dissector;
329
330 /* struct flow_keys_digest:
331 *
332 * This structure is used to hold a digest of the full flow keys. This is a
333 * larger "hash" of a flow to allow definitively matching specific flows where
334 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
335 * that it can be used in CB of skb (see sch_choke for an example).
336 */
337 #define FLOW_KEYS_DIGEST_LEN 16
338 struct flow_keys_digest {
339 u8 data[FLOW_KEYS_DIGEST_LEN];
340 };
341
342 void make_flow_keys_digest(struct flow_keys_digest *digest,
343 const struct flow_keys *flow);
344
flow_keys_have_l4(const struct flow_keys * keys)345 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
346 {
347 return (keys->ports.ports || keys->tags.flow_label);
348 }
349
350 u32 flow_hash_from_keys(struct flow_keys *keys);
351 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
352 struct flow_dissector_key_icmp *key_icmp,
353 void *data, int thoff, int hlen);
354
dissector_uses_key(const struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id)355 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
356 enum flow_dissector_key_id key_id)
357 {
358 return flow_dissector->used_keys & (1 << key_id);
359 }
360
skb_flow_dissector_target(struct flow_dissector * flow_dissector,enum flow_dissector_key_id key_id,void * target_container)361 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
362 enum flow_dissector_key_id key_id,
363 void *target_container)
364 {
365 return ((char *)target_container) + flow_dissector->offset[key_id];
366 }
367
368 struct bpf_flow_dissector {
369 struct bpf_flow_keys *flow_keys;
370 const struct sk_buff *skb;
371 void *data;
372 void *data_end;
373 };
374
375 static inline void
flow_dissector_init_keys(struct flow_dissector_key_control * key_control,struct flow_dissector_key_basic * key_basic)376 flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
377 struct flow_dissector_key_basic *key_basic)
378 {
379 memset(key_control, 0, sizeof(*key_control));
380 memset(key_basic, 0, sizeof(*key_basic));
381 }
382
383 #ifdef CONFIG_BPF_SYSCALL
384 int flow_dissector_bpf_prog_attach_check(struct net *net,
385 struct bpf_prog *prog);
386 #endif /* CONFIG_BPF_SYSCALL */
387
388 #endif
389